Thirty years ago on February 24, 1987, observers in the southern hemisphere noticed a new object in the Large Magellanic Cloud. Today, we know this object as Supernova 1987A, and it was one of the brightest supernova seen in hundreds of years. Coupled with its relative proximity at about 160,000 light years from Earth, Supernova 1987A became one of the best opportunities ever for astronomers to study the phases before, during, and after the death of a star.

Since its discovery, telescopes around the world and in space have observed Supernova 1987A. This includes NASA’s Chandra X-ray Observatory, which has looked at this object repeatedly during its 17 years of science operations.

From 1999 until 2013, Chandra data showed an expanding ring of X-ray emission that had been steadily getting brighter. This was produced by the blast wave from the original explosion that had been bursting through and heating the ring of gas surrounding the supernova.

In the past few years, there have been striking changes in the Chandra data. This provides evidence that the explosion’s blast wave has moved beyond the ring into a region with less dense gas. This represents the end of an era for SN 1987A. Since astronomers do not know exactly lies beyond the ring, they will be watching carefully what happens next.

Over the next few thousand years, the expanding shell of hot gas will continue to glow in X rays. Eventually after rumbling across several thousand light years, the shell will disperse. By doing this, the supernova spreads the heavy elements created in the star and possibly triggers the formation of new stars from a cold interstellar cloud. Using data from Chandra and other telescopes, astronomers will continue to learn more about the details of this very important process that is responsible for life as we know it.